Bending machine



Dec. 31, 1946. R. M. SHAW, JR

BENDING MACHINE Filed Sept. 17, 1943 2 Sheets-Sheet l Illlillllllll IZVDec. 31, 1946. v R., M. SHAW, JR 2,413,523

BENDING MACHINE Filed Sept. 17, 1943 2 SheetsSheet 2 BY g c/EOE;

'A'r EYS.

Patented Dec. 31, 1946 assum MAQHIN Balp h MqSl aw, Jr Edgelwater-Park,-- N. J assignor to Pedrick 'iool 85 Machine Company,Philadelphia', 21., a corporation of Pennsyl- "mania Ilanplicationtseptem e 1 Claim. (Cl. 5153746) This inventionrelatesstemach es usefu i bendin barscr tubes and jghas reference moreparticularly to. bending machines of the" type disclosed in U. S. PatentNo. 2,266,912, granted .to m on.Decemb r 23, 9% V My presentmachinehas'for its chief aim to enable, through structural improvementsand refinements such as hereinafter illustrated and described,fashioning in machines of the kind referred to, of straightbars or tubesinto complete circles or even into spira-ls without inci-'dentaldeformationof their original cross sectional-configurationsonmarring of their surfaces.

How-the foregoing desideratum as well as other Qobjects'andattendant.advantages can be readily .wr'ealized' in practice .will appear .iromthe following. detailed description :of ,the {accompanying drawings,wherein i is,. 1, shows in top splan a;ben it m ch onv ni ntly .em edyng :m -.:pr s n i v o Fig. 3 isa perspective view of were the dieMmembersof the machine.

F, Eigs. 4- and-:5 are views .like l iigs .1 on. a smaller scale showingsuccessive steps in .the' bending' 194o3l er alNe, 592573 Y Y 2 2 -2fora tube T, which is to be bent, is supportedby the bed In On the topedge margin thereof.

"Instead of being circular as in the patent supra, -the stationary dieelement I5 is in the form of a sector which comprehends an arc of lessthan l80 t o be more exact of about 135- and which iskeyed to the stud Mat 23 so as to Eig.- 6 shows; a c o mplete circular loop formed I in atube'a'fter a 'few passes in the machine; and

Fig. 7 shows a spiral such as will result by continuing the bendingafter the stage shown in Fig. 6 has been reached.

Except as hereinafter particularly pointed out, the improved bendingmachine is generally like that disclosed in my above mentioned patent,said machine including a bed plate It] whereinto is recessed a rotatabledisk II with peripheral teeth 42 engaged by a driving pinion I3. Fixedin the bed plate l0 and passing through an axial opening in the disk IIis a cylindric post M which is diametrically reduced at its top andthere supports a stationary die member l5. Fulbe-ireadily, removable forsubstitution of similar die; members of different sizes and/or shapes.

1 l\ loreover, in accordance with my present inentiqn the e i ie i l imem 1' a t elrd e ero v 225 in it ,a at ed pe ltien wh c in theillustrated instance gs of "U. haped r ee t fi ei eeene. l; hise fig-i iin i e upw dl t th 91? e tai em entrant end 2 lie t I mi ia end at "2Als i a ord ce .With my present invention the complemental movable diente io sho i i .o a len some e excess of the arcuate peripheral extentof the stationa y d emembe l5. an p d .Wit

'. Q e' tud na1 rids "28 at i inn side, aid r d be n .Iof awidt ftp nuglen a e, W thinth "srneve 7.25 v e said, nonotat n die member.,Eroin-zfi'issh2and 3 it, wi e ,.no ,.,th t.i th ,rree n k nst n the id.2 t sh e 2! is concaveden wi h the rounded bott m o th groove 25 in thenon rotating die member l5 defines a die opening of circular crosssection corresponding to that of the tube T.

The holder 22 is of novel construction in that it comprises a splitclamp 30 with winged jamb crumed on the 'post I4 below the stationarydie member I 5 is an arm I6, which, adjacent its outer end, isreleasably secured by a latch pin I! to the top of the disk H so as torotate with the latter. As shown, the arm I6 carries a follower rollerl8 which is revolvably and axially free on a stud l9 capable ofadjustment along a longitudinal slot 20 in said arm. The follower rollerl8 bears against a straight elongate shoe 2| which constitutes themovable complemental or mating die member of the machine and cooperateswith the stationary die member I5 in efiecting the bending. The holderindicated at nuts SI; and a supporting block 32 with a pendent stud 33which slidingly fits into a socket hole in the top of the bed plate H),as well as with a vertical slot 34 for the free reception of a lateralstud projection 35 on the clamp 38. As a consequence of thisconstruction, the holder 22 is free to swivel and to rise and fallduring the bending while restraining endwise movement of the tube T; or,in other words said holder restr-ains the tube T. a

The operation of the machine is as follows: In preparation for thebending the disk I I is rotated to bring the arm IB into the full lineposition P inFig. l; the bar or tube T is secured in the holder 22 sothat the distance from the ex- 3 by the curved arrow in Fig. 1 throughan arc of 135 when the arm IE will have reached the position P in whichit is indicated in dot-and-dash lines in said figure. As a consequenceof the travel of the follower roller la in a circular orbit concentricwith the arcuate edge of the stationary die member l5, the shoe 2| willassume difierent angular positions tangentially to said edge and causethe extended end portion of the tube clination of the groove 25, in saiddie member,

this action being facilitated by reason of the axial freedom of thefollower roller l8 on its supporting stud I9 and by virtue of theability of the holder 22 to swivel as well as to rise and fall inaccommodating lateral movements of the re- .strained end portion of thetube T. With the first bend completed, the disk II is reversely rotatedand returned to its original position P whereupon the bar or tube isshifted as shown .in Fig. 4 by a distance corresponding in magnitude tothe peripheral extent of the stationary die .member 15 and again clampedby the holder 22.

The above described cycle of the machine is then repeated to move thearm I 6 fromthe position 'P to the position P in Fig. 4 thereby addingan- ,other 135 bend to the bend made in the first pass of the tube T- inthe machine. After the formation of the second bend, the arm 16 is againreturned to the position P as shown in Fig. 5 and the tube T once moreshifted and re-clamped in the holder 22 for a third pass by which thearm I6 is a third time moved from the. full line position to thedot-.and-dash lineposition P.

the last described pass still another 135 is added, 'to the curvaturesformed in the previous passes,

so that somewhat more than a complete circular loop results as shown inFig. 6. By further repetitions of the above procedure, it isobviously'possible to fashion the tube into a coil such as shown in Fig.7 which can be subdivided into a number of individual split ring blanksby cutting the same at one side along a line X-Y. After the cutting, theends of the individual ring blanks are brought into line and weldedorotherwise united to close the rings. The use of a stationary die ofless than a half circle such as herein featured, is advantageous in thatit permits ready removal of the work from the machine at any stage ofthe bending.

Solid bars of circular cross section of course lend themselves to readybending in my improved machine in the form in which it is hereinillustrated by way of example. Furthermore, by appropriately profilingthe opposing faces of the cooperative die members l5 and 2| it will beapparent to those skilled in the art that my improved machine can beadapted for bending bars or tubes of other cross sectional shapes within'the scope of the appended claim;

Having thus described my invention, I claim:

A machine for spirally bending bars, tubes or the like, comprising incombination a stationary die member in the form of a sector having arelatively deep inclined groove in its peripheral edge;

a complemental movable die member in the form of a straight elongateshoe having a longitudinal ridge for snug engagementwithin the outeredge limits of the inclined groove of the stationary die member tojointly form an opening conformatory with the cross-section of the baror tube to be 'bent; a holder comprising a split-clamp and a pivotalsupporting-block, said split-clamp having 'a projection slidablyengaging a vertical slot in the supporting-block, thus enablingswiveling and vertica1 movement of the holder while positivelyrestraining endwise movement of the bar or tube during the bendingoperation; and a follower roller movable in a circular orbit concentricwith the edge of the stationary die member, whereby the elongate shoeassumes different angular positions'tangential to the peripheral edge ofthe stationary die member and progressively depresses the bar or tubeinto the inclined groove of said stationary die member. RALPH M. SHAW,JR.

